This invention relates to methods and apparatus for changing sizes in pull-on absorbent personal care articles. More specifically, this invention relates to methods and apparatus for changing sizes in especially the circumferential waist in pull-on refastenable absorbent personal care articles. The methods and apparatus of the invention nullify the counterproductive aspects of down time on manufacturing lines to change and adjust function rolls and other components necessary for changing production from a first article size to a second different article size, of pull-on refastenable absorbent personal care articles.
In conventional methods for fabricating disposable pull-on refastenable absorbent personal care articles of differing sizes, it is known to stop manufacturing line production of personal care articles of a first size to replace and/or reposition function rolls and adjust timing of manufacturing line components to produce personal care articles of a second different size on the same manufacturing line. The down time associated with a conventional such production change-over is typically significant. The main reason for such significant down time is related to conventional methods of changing the product length to effect change in product (e.g. waist) size.
Function rolls are typically either exchanged or moved to compensate for a variety of lengths of any of front portions, back portions, and crotch portions of such absorbent articles, defining differing waist, and optionally crotch, sizes between the first and second sizes of absorbent personal care articles. Similarly, other manufacturing components are typically adapted, for example, knife repeat distances may be adjusted, or a knife or knives may be moved, to compensate for changed cutting requirements. Timing of front fastener panel applicators and hook tab fastener applicators may also need to be adjusted in a machine direction to compensate for waist size differentiation between different sizes of absorbent articles. In sum, the conventional method of making a size change is to shut down the production line and physically adjust or move selected machines in order to effect the change to making a second different size of personal care absorbent article.
A need exists for methods and apparatus for production of pull-on refastenable absorbent personal care articles wherein the methods and apparatus reduce the number of manufacturing elements which must be moved or adjusted, and thereby attenuate down time on a manufacturing line as well as reduce cost to manufacturers by enabling manufacturers to use common manufacturing line components to producing pull-on refastenable absorbent personal care articles having a variety of sizes.
Thus it is an object of this invention to provide methods and apparatus for production of pull-on absorbent personal care articles while attenuating down time on a manufacturing line, as well as to reduce cost to manufacturers by allowing manufacturers to use the same manufacturing line components in producing at least two sizes of pull-on refastenable absorbent personal care articles.
It is another object to provide methods and apparatus for changing product size without changing machine direction product repeat length.
It is a further object to provide methods and apparatus for changing spacing between a landing zone loop structure and cooperating fasteners of personal care articles.
It is still a further object to provide methods and apparatus for changing location of the fastener portion on the front portion of personal care articles.
In a first family of embodiments, the invention comprehends a method of changing from manufacture of pant-type refastenable personal care articles of a first size to manufacture of such pant-type refastenable personal care articles of a second different size. The method takes place in a process for manufacturing pant-type refastenable personal care articles in a format which includes defining a stream of workpieces connected to each other along a web having an indefinite length. A respective such personal care article has a front portion, a rear portion, and a crotch portion. The method comprises, with respect to each work piece, defining in the web or workpiece a length of material defined in a machine direction wherein activity of such length of material, in combination with other elements of the web or workpiece, determines the size of the pant-like personal care article being so produced, whereby the length of material can be activated to thereby produce relatively larger such personal care articles, or inactivated to produce relatively smaller personal care articles. The method also comprises changing activity of the lengths of material so defined, thereby to affect size change in the respective personal care articles being produced while maintaining the so-defined lengths of material in the web at least until the respective work pieces are separated from the web.
In preferred embodiments, the method includes such workpieces, including the defined length of material, having a common dimension leading edge to leading edge, in the machine direction of such manufacturing process both with inclusion of the length of material and with exclusion of the length of material.
In a second family of embodiments, the invention comprises a method of changing from manufacture of pant-type refastenable articles of a first size to manufacture of such pant-type refastenable articles of a second different size in a process for manufacturing pant-type refastenable personal care articles. A respective such personal care article has a front portion, a rear portion, and a crotch portion. The personal care article also has a fastener-receptive area at the front portion for receiving fasteners thereon, first and second fasteners on opposing sides of the fastener-receptive area, and first and second lines of weakness on opposing sides of the fastener-receptive area and between the fastener-receptive area and the respective first and second fasteners. The first and second lines of weakness can be employed for tearing first and second lateral sections from a central section of the front portion, whereby the first and second fasteners are disposed on the respective first and second lateral sections. The method of changing from manufacture of such pant-type refastenable articles of a first size to manufacture of such pant-type refastenable articles of a second different size, in the manufacturing process, comprises changing spacing between the fastener-receptive area and at least one of the first and second fasteners while maintaining the first and second lines of weakness between the fastener-receptive area and the respective first and second fasteners.
In preferred embodiments, the method includes changing spacing between the fastener-receptive area and both of the first and second fasteners while maintaining the first and second lines of weakness between the fastener-receptive area and the first and second fasteners.
In some embodiments, the method includes changing location of one or both of the respective fasteners on the front portion.
In some embodiments, the method includes changing location of one or both of the respective lines of weakness to maintain spacing between the line or lines of weakness and the respective fastener or fasteners.
In some embodiments, the fastener-receptive area has first and second side edges facing the respective first and second fasteners, and the method includes changing location of at least one of the side edges of the fastener-receptive area, and can include changing location of the respective line of weakness to maintain spacing between the line of weakness and the respective side edge.
In preferred embodiments, the method includes changing locations of both the first and second side edges of the landing zone, and can include changing locations of the lines of weakness to maintain spacing between the respective lines of weakness and the respective side edges.
In a third family of embodiments, the invention comprehends a method of changing from manufacture of pant-type refastenable articles of a first size to manufacture of such pant-type refastenable articles of a second different size, wherein the method comprises changing location of at least one of the first and second fasteners toward or away from the central longitudinal axis while maintaining the respective first or second line of weakness between the respective fastener and the central longitudinal axis. In a process for manufacturing such pant-type refastenable personal care articles, a respective such personal care article has first and second lines of weakness defining first and second side edges of the landing zone, whereby the first and second fasteners are disposed on the respective first and second lateral sections, and the central section of the front portion between the lines of weakness defines the landing zone.
In a fourth family of embodiments, the invention comprehends a method employed in a process for manufacturing pant-type refastenable personal care articles, the process including utilizing first feed apparatus and corresponding first feed settings to feed fasteners to work pieces, and optionally utilizing second feed apparatus and corresponding second feed settings to feed fastener-receptive areas to the work pieces. The method includes at least one of (i) changing the feed settings of the feed apparatus feeding the fasteners to thereby move the locations on the work pieces, of placement of the fasteners, and (ii) relocating the apparatus feeding the fasteners to the work pieces, to thereby move the locations on the work pieces, of placement of the fasteners.
In some embodiments, the process includes cutter apparatus fabricating the lines of weakness in the front portion, the method further comprising relocating the cutter apparatus to thereby move the locations on the work pieces, of fabricating the lines of weakness, or changing the timing of cutting of the lines of weakness to thereby move the locations on the work pieces, of fabricating the lines of weakness.
In some embodiments, the method includes changing the timing of the feed apparatus feeding the fasteners to the work pieces, thereby to move the locations on the work pieces, of placement of the fasteners, while running a manufacturing line and so producing such pant-type refastenable personal care articles.
In a fifth family of embodiments, the invention comprehends a method of manufacturing personal care articles comprising manufacturing an indefinite number of personal care articles of a first size, and reducing size of the personal care articles being manufactured by changing, in each respective personal care article, spacing between respective elements in the front portion of the personal care article and thereby creating excess material in an element represented in the front portion.
In some embodiments, the method includes retaining the excess material in the personal care articles through completion of manufacture, and packaging.
Yet in other embodiments, the method includes removing the excess material in the personal care articles at some point during manufacture, and packaging.
In a sixth family of embodiments, the invention comprehends a pant-type refastenable personal care article having a front portion and a rear portion, and a crotch portion between the front portion and the rear portion. Each of the front and rear portions comprises first and second side edges. The pant-type refastenable personal care article comprises an outer liquid-impermeable cover, an inner liquid-permeable liner, and an absorbent core disposed between the outer cover and inner liner. The pant-type refastenable personal care article has a first length represented by a first distance across a front portion of the pant-type refastenable personal care article, and a second length represented by a second distance across a rear portion of the pant-type refastenable personal care article. The pant-type refastenable personal care article comprises a landing zone disposed at a portion of the front portion of the outer cover, first and second fasteners, each disposed laterally of the landing zone, and first, second, third, and fourth lines of weakness. The first line of weakness and the third line of weakness are disposed between the landing zone and the first fastener. The second line of weakness and the fourth line of weakness are disposed between the landing zone and the second fastener. The portion of the pant-type refastenable personal care article disposed between the first and third lines of weakness defines a first length of material, and the portion of the pant-type refastenable personal care article disposed between the second and fourth lines of weakness defines a second length of material.
In preferred embodiments, the invention further comprises a third fastener disposed on the first length of material, and a fourth fastener disposed on the second length of material.
In some embodiments, the first length of material and second length of material remain attached to the personal care article while the personal care article is being worn by a wearer.
In other embodiments, the first length of material and second length of material are removed by a wearer of the personal care article.
Yet in other embodiments, the first length of material and second length of material are removed by a manufacturer of the personal care article.